The present invention relates to attachment of windscreen wiper blades to windscreen wiper arms. More specifically the present invention relates to attachment of a wiper blade to a wiper arm by means of a pin which extends from the wiper arm, the pin extending generally transversely to the direction of extension of the wiper arm. The wiper blade has an aperture therethrough in a direction generally perpendicular to the longitudinal extent of the wiper blade and the pin is inserted into the aperture so that the blade is attached to the wiper arm in a manner enabling at least a limited rotation of the wiper blade about the pin. The present invention relates particularly to the means by which the pin is attached or secured in the wiper blade aperture.
In the prior art numerous arrangements have been utilized for securing the pin within the wiper blade aperture. Australian Pat. No. 261,354 to Trico Products Corporation discloses a wiper arm having a channel shaped member having side portions through which a transverse pin passes from a wiper arm clip. The clip is releasably mounted to a wiper arm but the pin is permanently secured to the wiper blade and the clip.
Australian Pat. No. 406,236 to Trico Products Corp. discloses an arm and wiper blade assembly wherein a connector pin, fixed to the arm, has a reduced diameter center portion and the pin engages aligned apertures in side walls of the wiper blade. A receptor comprising a tubular member and a coiled spring are arranged to engage with the reduced diameter portion of the pin to prevent removal of the wiper blade therefrom.
Australian Pat. No. 420,822 to Trico Products Corp. discloses the use of a leaf spring to engage a reduced diameter portion of the pin to retain the pin and wiper arm engagement.
Australian Pat. No. 433,044 to Trico Products Corp. discloses an arrangement of coil spring and tubular member similar to that of Australian Pat. No. 406,236. Australian Pat. No. 439,186 to Trico-Folberth Limited discloses modified arrangements of the leaf-spring latching and coil spring latching similar to those of the Australian Pat. Nos. 406,236 and 420,822.
Australian Pat. No. 468,102 to The Anderson Company shows further modified latching arrangements using a leaf spring engaging a reduced diameter portion of the pin.
Australian Patent Application No. 54603/73 of Robert Bosch (Australia) Pty. Ltd. discloses another form of latching arrangement having a spring biased slide in the wiper blade which is movable under the spring bias to engage the reduced diameter portion of the pin to secure the pin in the wiper blade.
As is shown in the prior art arrangements, the pin is usually provided with a reduced diameter portion (otherwise described as a recess or channel) having shoulders on each side thereof. The pin has, in the past, been secured within the wiper blade aperture by location of biasable latching elements, coil springs or other insertable members into the reduced diameter portion of the pin. These prior art arrangements are disadvantageous in that use of an auxiliary tool such as a screwdriver is required for attachment or disassembly or in that a plurality of parts need to be assembled and secured together prior to insertion of the pin into the aperture.
It would therefore be desirable to provide a new arrangement whereby a single element can be used to releasably secure a wiper blade to a wiper arm and which preferably enables ready attachment and disassembly without requiring use of any tools.